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1 oblige keyboard_arrow_downkeyboard_arrow_up
/oblige/ [ah0.b.l.ay1.jh]

Definition: force somebody to do something

Example sentences:

  • At a company with publicly traded stock, management and controlling holders are obliged to put public shareholders’ interests above their own.
  • The government plans to oblige mobile operators to improve their coverage, possibly by sharing rivals' networks.

2 oblivious keyboard_arrow_downkeyboard_arrow_up
/obliv-i-ous/ [ah0.b.l.ih1.v.iy0.ah0.s]

If you are oblivious to something or oblivious of it, you are not aware of it.

Example sentences:

  • She kept dancing, oblivious to everyone around her.
3 obstruct keyboard_arrow_downkeyboard_arrow_up
/ob-struct/ [ah0.b.s.t.r.ah1.k.t]

Definition: Prevent or hinder (movement or someone or something in motion)

Example sentences:

  • If protest demonstrations and rallies can be confined to select areas and organised peacefully without obstructing the free movement of others, nobody can complain.

4 occupation keyboard_arrow_downkeyboard_arrow_up
/oc-cu-pa-tion/ []

"Occupation" means a person's job or profession. For example:

  • He is thinking about changing occupations and becoming a police officer.
  • Many of his colleagues have taken up another occupation.
  • Our recent graduates have entered a wide range of occupations.

"Occupation"  can also mean an activity that a person spends time doing. For example:

  • His favorite occupation [=pastime] is playing chess.

"Occupation" can also mean the activity of living in or using a particular place. For example:

  • Some evidence of human occupation was found in these caves.



have an occupation

  • The people in the region have a variety of occupations.

choose an occupation

  • Young people need help with choosing a suitable occupation.

take up an occupation = enter an occupation

  • Many of his colleagues have taken up another occupation.
  • Our recent graduates have entered a wide range of occupations.

manual occupations/blue-collar occupations  (=jobs in which you work using your hands)

  • People from manual occupations are most at risk of experiencing poverty.

professional occupations/white-collar occupations(=jobs that usually involve a lot of education)

  • Teachers’ pay compares poorly with that of other white-collar occupations.

skilled/unskilled occupations (=needing training and experience/not needing training and experience)

  • Plumbing and carpentry are highly skilled occupations.
  • Workers in unskilled occupations are finding fewer job opportunities.

a working-class/middle-class occupation

  • Teaching is regarded as a middle-class occupation.
  • Working-class occupations may be divided into skilled, semi-skilled and unskilled.

managerial occupations (=a job that involves being a manager)

  • Women in managerial occupations tend to have children later.

service occupations (=a job in which you provide a service rather than producing goods)

  • Around two-thirds of the labor force is employed in service occupations.





5 occur keyboard_arrow_downkeyboard_arrow_up
/oc-cur/ [ah0.k.er1]

Definition: take place;happen

Example sentences:

  • An air bag is designed to protect a driver or passenger in the event that an accident occurs.

6 octopus keyboard_arrow_downkeyboard_arrow_up
/oc-to-pus/ [aa1.k.t.ah0.p.uh2.s]

Definition: A cephalopod mollusc with eight sucker-bearing arms, a soft sac-like body, strong beak-like jaws, and no internal shell.

Example sentences:

  • The harbor seal's diet consists of fish, cephalopods, such as octopus and squid, and crustaceans.

7 offspring keyboard_arrow_downkeyboard_arrow_up
/off-spring/ []

You can refer to a person's children or to an animal's young as their offspring. 

Example sentences:

  • Penguins congregate in groups to stay warm. With their group congregations, they are able to reproduce their offspring in extremely cold temperatures.

  • Typically, crossbreeding is done because it can help the offspring gain important traits, such as resistance to disease, different colors in the cases of flowers, or enhanced productivity or nutritional value.

8 omnivore keyboard_arrow_downkeyboard_arrow_up
/om-ni-vore/ [no ipa available]

An omnivore is a kind of animal that eats either other animals or plants. Some omnivores will hunt and eat their food, like carnivores, eating herbivores and other omnivores. Some others are scavengers and will eat dead matter. Many will eat eggs from other animals.

9 onset keyboard_arrow_downkeyboard_arrow_up
/on-set/ [aa1.n.s.eh2.t]

Definition: The beginning of something, especially something unpleasant:

Example sentences:

  • The onset of winter appears to have been delayed, throwing many plants into confusion.

10 optical illusion keyboard_arrow_downkeyboard_arrow_up
/op-ti-cal il-lu-sion/ [no ipa available]

Definition: Something that deceives the eye by appearing to be other than it is

Example sentences:

  • Consider the famous optical illusion of two identical lines where one has concave triangles at its edges whilst the other has convex triangles at either end.

11 orbital keyboard_arrow_downkeyboard_arrow_up
/or-bital/ [ao1.r.b.ah0.t.ah0.l]

"Orbital" describes things relating to the orbit of an object in space. 

Example sentences:

  • The newly discovered world followed an orbital path unlike that of any other planet.
  • The orbital period of the moon is 27 days.
  • Earth's orbital speed averages about 30 km/s.


12 originality keyboard_arrow_downkeyboard_arrow_up
/orig-i-nal-i-ty/ [er0.ih2.jh.ah0.n.ae1.l.ih0.t.iy0]

Originality is the quality of being new and inventive. A composer who writes a symphony to be played by car horns and cell phones shows great originality.  A great artist is full of originality, especially when coming up with new and surprising types of art. If something is just like other things, it shows no originality. 

Example sentences:

  • Critics have praised the movie's startling originality.
  • I was amazed by the originality of her ideas.


have originality

·         This book does not have the originality and power of his first novel.

show originality

  • His research shows originality and sustained effort.

lack originality

  • The music lacks originality, but is fun and well-played.

a spark of originality (=a small amount of originality)

  • The show at least has a spark of originality, something that most TV programs seem to lack.

13 originated keyboard_arrow_downkeyboard_arrow_up
/orig-i-nat-ed/ [er0.ih1.jh.ah0.n.ey2.t.ah0.d]

When something originates or when someone originates it, it begins to happen or exist.

Example sentences:

  • You can originate the idea of adding a fancy new coffee machine to your company's break room.
  • A carpet that originates in Turkey can travel all the way to an apartment in New York. The soya bean originated in China, is used it as 'green manure' to enrich the soil for growing other crops.
  • The continental crust is thought to have originated from the movement of magma when plate tectonics first formed billions of years ago.
  • Jupiter's moons most likely originated from passing asteroids that were captured into orbit. 
14 oscillate keyboard_arrow_downkeyboard_arrow_up
/os-cil-late/ [aa1.s.ah0.l.ey2.t]

Definition: Vary in magnitude or position in a regular manner about a central point

Example sentences:

  • The light made the electrons in each atom oscillate back and forth from one side of the atom to the other

15 outcome keyboard_arrow_downkeyboard_arrow_up
/out-come/ [aw1.t.k.ah2.m]

People often confuse outcome and result.

"Result" is often used to talk about things that are caused directly by something else. "Outcome" is more often used to talk about what happens at the end of a process when the exact relation of cause and effect is less clear. 

in addition, "result" is often used after an event to talk about what happened. "Outcome" is often used before an action or process to talk about what is likely to happen.”


Take a look at these examples

  • The outcome of a pricing strategy may be less profit from a reduced number of sales.
  • It's too early to predict the outcome of the meeting.
  • We are waiting to hear the final outcome of the negotiations.
  • I know that my students worked hard, so I expect a good outcome.
16 outlet keyboard_arrow_downkeyboard_arrow_up
/out-let/ [aw1.t.l.eh2.t]

Definition: A point from which goods are sold or distributed

Example sentences:

  • This is where the young hang out, in coffee shops, fast-food outlets, shopping malls and on the street itself.

17 outweigh keyboard_arrow_downkeyboard_arrow_up
/out-weigh/ [aw1.t.w.ey2]

To outweigh is to be more important than something (or someone).  If someone says "the benefits outweigh the risks," they mean that what can be gained is much more significant than what might be lost or risked. For example, "I think you should apply for that scholarship; the benefits really outweigh the risks​​"

Example sentences using the word “outweigh”:

  • She outweighs her sister by 10 pounds.
  • The advantages far outweigh the disadvantages.
  • This issue outweighs all others in importance.
  • The benefits would surely far outweigh the risks.
  • In summary, I believe that the benefits of having young people undertake community service would far outweigh any disadvantages.
  • For most people, the pros outweigh the cons and online shopping is as normal to them as any other daily activity.
  • To what extent do the advantages of this outweigh the disadvantages?

Remember - if one thing outweighs another, the first thing is of greater importance, benefit, or significance than the second thing.


18 overestimate keyboard_arrow_downkeyboard_arrow_up
/over-es-ti-mate/ [ow2.v.er0.eh1.s.t.ah0.m.ey2.t]

When you estimate something, you make a calculation or a judgment of its value. So, when you overestimate, you assign too much value to the thing you are judging. If you overestimate how much time you have left to get to school, you could be late. Likewise, if you overestimate how prepared you are for a test; you might end up with a poor grade. This verb is the opposite of underestimate, or “to assign too little value.”

Here are some example sentences using the word “overestimate”:

  • I overestimated the number of chairs we would need for the party. (This means I thought we would need more chairs than we actually did)
  • We overestimated the value of the coins.

Please be aware that in the above examples the word “overestimate” is followed by an object.

The word overestimate can also mean to think of (someone or something) as being greater in ability, influence, or value than that person or thing actually is. Example sentences are as follows:

  • She overestimated his ability to do the job.
  • The importance of a good education cannot be overestimated. (This means a good education is very important)

Overestimate can also be used in the plural form: overestimates which is a countable noun.

Example sentence:

  •  Cost overestimates in the budget left us with extra money in the end.


19 overfish keyboard_arrow_downkeyboard_arrow_up
/over-fish/ []

Definition: Deplete the stock of fish in (a body of water) by excessive fishing

Example sentences:

  • Seventy percent of the world's most valuable fisheries, and 11 of 15 major fishing grounds, are either overfished or fished to the limit according to the United Nations.

20 overlook keyboard_arrow_downkeyboard_arrow_up
/over-look/ [ow1.v.er0.l.uh2.k]

Definition: look down on; to ignore or neglect

Example sentences:

  • The glass walls of their common room overlook the main hall and dining area.
  • Scientists must not overlook any aspect of experimental procedure.

21 oversimplify keyboard_arrow_downkeyboard_arrow_up
/over-sim-pli-fy/ [ow0.v.er0.s.ih1.m.p.l.ih0.f.ay2]

Definition: (often as adjective oversimplified);Simplify (something) so much that a distorted impression of it is given

Example sentences:

  • This desire for social engineering shows that the Treasury has a caricatured and oversimplified idea of the world outside, as one would expect from people widely insulated from real life.

22 overtly keyboard_arrow_downkeyboard_arrow_up
/overt-ly/ [ow0.v.er1.t.l.iy0]

Definition: in a way clearly seen; not done secretly

Example sentences:

  • It is important as a scientist, irrespective of belief, to be as objective as possible and steer clear of overtly political, advocacy, or activist stances.

23 oviparous keyboard_arrow_downkeyboard_arrow_up
/oviparous/ [ow0.v.ih1.p.er0.ah0.s]

Oviparous animals are animals that lay eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, reptiles, all birds, and the monotremes.

24 oblique keyboard_arrow_downkeyboard_arrow_up
/oblique/ [ah0.b.l.iy1.k]

Definition: Neither parallel nor at right angles to a specified or implied line; slanting

Example sentences:

  • We sat on the settee oblique to the fireplace

25 obscure keyboard_arrow_downkeyboard_arrow_up
/ob-scure/ [ah0.b.s.k.y.uh1.r]

Radio telescopes can detect invisible gas, and can reveal areas of space that may be obscured with cosmic dust.

26 occupant keyboard_arrow_downkeyboard_arrow_up
/oc-cu-pant/ [aa1.k.y.ah0.p.ah0.n.t]

An occupant is someone who lives or stays at a place for a while. Being an occupant means you're occupying a place. This has nothing to do with owning a house or renting an apartment; if you live there, you're an occupant.

Example sentences:

  • The apartment's previous occupant was a painter.
  • Both of the car's occupants were injured.
  • Most of the occupants had left before the fire broke out
27 occupational keyboard_arrow_downkeyboard_arrow_up
/oc-cu-pa-tion-al/ []

If it has anything to do with your job, your work or your career, then you can describe it as occupational. You might hear people talk about "occupational hazards" — which can range from paper cuts to falling trees, depending on if you make a living filing or lumber-jacking.

Example sentences:

  • The firefighters' workplace was filled with occupational hazards.
  • Some received substantial occupational assistance in the form of low-interest loans.
  • The program offered free occupational training to the poor.
  • Hand injuries are an occupational hazard for typists. (meaning typists are likely to have hand injuries because of the work they do)


28 oceanic keyboard_arrow_downkeyboard_arrow_up
/ocean-ic/ []

Definition: Relating to the ocean

Example senences:

  • The occurrence of major pulses of oceanic water has proved unpredictable, being non-existent during the 1980s. The two eastern forks of Long Island jut into oceanic waters, creating a mixing zone for currents and coastal and offshore migratory species.


29 odors keyboard_arrow_downkeyboard_arrow_up
/odors/ [ow1.d.er0.z]

Definition: A distinctive smell, especially an unpleasant one

Example sentences:

  • During that time, the officer had smelled the odour of alcohol on the accused's breath.

30 omit keyboard_arrow_downkeyboard_arrow_up
/omit/ [ow0.m.ih1.t]

Definition: leave undone or leave out

Example sentences:

  • The sequence omits whole classes of genes found in all other animals, including genes normally involved in immunity, develop­ment and neural function.
  • This almost instant cucumber kimchi can be made in no time, omitting the fermentation process.

31 on account of keyboard_arrow_downkeyboard_arrow_up
/on ac-count of/ [no ipa available]

You use "on account of" to introduce the reason or explanation for something. "Because of" and "on account of' are synonymous in cases where reasons involve thoughts or records.   Here is an example sentence:

  • We canceled the beach picnic on account of the bad weather forecast.

Let's look at the following two sentences:

  • The water boiled because of the heat. (Better!)
  • The water boiled on account of the heat. 

Both uses are valid, but in this example, because of is slightly better than on account of because it does not imply thought on the part of the water.

32 oppression keyboard_arrow_downkeyboard_arrow_up
/op-pres-sion/ []

Oppression is when a group or a person takes power and controls the people with less power in a cruel or unfair way. Oppression is the act of using power in a hurtful way. If your grandparents lived through oppression, they have likely lived very hard days, and deserve a great deal of respect.

  • Nowadays, you often hear more and more about the oppression of Native Americans by the pilgrims.

33 orbit keyboard_arrow_downkeyboard_arrow_up
/or-bit/ [ao1.r.b.ah0.t]

If something such as a satellite orbits a planet, moon, or sun, it goes around it in a continuous, curving path.

These phrases "go around, revolve around, be in orbit around" have the same meaning of  “orbit”.

Look at this sentence:

  • Planets go around the sun.

We can paraphrase it to

  • Planets orbit the sun.
  • Planets revolve around the sun.
  • Planets are in orbit around the sun.
34 origin keyboard_arrow_downkeyboard_arrow_up
/ori-gin/ [ao1.r.ah0.jh.ah0.n]

An origin is a start. You could say that the origin of yoga was in India, since that's where the practice began, or that the origin of the strawberries in the market is Mexico since they were grown there.Your ancestry is another kind of origin — you might mention your Eastern European origin if that's where your ancestors came from. The phrase "in origin" is used.

Example sentences:

  • The origin of this custom/tradition is not known.
  • Their medical problems are basically physical in origin.
  • Her family is Portuguese in origin.
  • The rock is volcanic in origin.
35 originate keyboard_arrow_downkeyboard_arrow_up
/orig-i-nate/ [er0.ih1.jh.ah0.n.ey2.t]

When something originates or when someone originates it, it begins to happen or exist.

Example sentences:

  • You can originate the idea of adding a fancy new coffee machine to your company's break room.
  • A carpet that originates in Turkey can travel all the way to an apartment in New York. The soya bean originated in China is used as 'green manure' to enrich the soil for growing other crops.
  • The continental crust is thought to have originated from the movement of magma when plate tectonics first formed billions of years ago.
  • Jupiter's moons most likely originated from passing asteroids that were captured into orbit. 


36 ornamentation keyboard_arrow_downkeyboard_arrow_up
/or-na-men-ta-tion/ []

Ornamentation can be referred to as the materials used for decoration. Ornamentation is typically used to make something pretty, or fancier. Try to remember this word by thinking of Christmas ornaments that people use to make their Christmas tree look more beautiful.


37 out-of-date keyboard_arrow_downkeyboard_arrow_up
/out-of-date/ [no ipa available]

Something that's out-of-date is either old-fashioned or so old that it's invalid. An expired driver's license is out-of-date, and the out-of-date milk in your refrigerator is pretty likely to smell sour.  Another way to be out-of-date is to be hopelessly unfashionable, like grandparents' out-of-date kitchen, with its appliances from 1970. You can also use the words obsolete or outdated as synonyms for out-of-date, for most things.

38 outlaw keyboard_arrow_downkeyboard_arrow_up
/out-law/ [aw1.t.l.ao2]

Definition: Ban; make illegal:

Example sentences:

  • The legislation is not there to tackle discriminatory treatment but to outlaw sex discrimination.

39 outperform keyboard_arrow_downkeyboard_arrow_up
/out-per-form/ [aw1.t.p.er0.f.ao2.r.m]

Definition: Perform better than

Example sentences:

  • Other researchers have found that when essay exams are used to evaluate performance, women outperformed their male counterparts.

40 overcome keyboard_arrow_downkeyboard_arrow_up
/over-come/ [ow1.v.er0.k.ah2.m]

Use the verb overcome when you talk about someone who has triumphed over adversity. You can also be overcome with emotions, or overwhelmed by your feelings. Many people feel so overcome with sadness at a movie — or happiness at a wedding. The verb overcome also means to win or surpass. If you are going to win the marathon, you are going to have to overcome the five runners still ahead of you.

Example sentences of the word overcome:

  • After a tough battle, they overcame the enemy.
  • She overcame a leg injury and is back running again.
  • He overcame his fear of heights and climbed the ladder.
  • To succeed, one must overcome obstacles.

The phrases “to be overcome by” and “to be overcome with” are often used.

The phrasal verb “be overcome with” means to be strongly affected by an emotion or a feeling. For example:

  • After his dog died, Danny was overcome with grief.
  • The whole team was overcome with the joy of winning and being champions.
  • He was suddenly overcome with remorse for the harm he had done.

For the phrasal verb “be overcome by”,  if you are overcome by a feeling or event, it is so strong or has such a strong effect that you cannot think clearly. For example:

  • The night before the test I was overcome by nervousness.
  • The family was overcome by grief.

If you are overcome by smoke or a poisonous gas, you become very ill or die from breathing it in.  For example:

  • The residents were trying to escape from the fire but were overcome by smoke. 
  • Several firefighters had been overcome by smoke and fumes.
  • Five employees were overcome by smoke.

Difficulties/obstacles can be overcome by efforts. For example:

  • These difficulties were overcome by the efforts of devoted officers.
41 overexpose keyboard_arrow_downkeyboard_arrow_up
/over-ex-pose/ [ow2.v.er0.ih0.k.s.p.ow1.z]

Definition: Expose too much, especially to the public eye or to risk:

Example sentences:

  • The dollar pessimists argue that the Asian central banks are already dangerously overexposed both to the dollar and to the U.S. bond market

42 overflow keyboard_arrow_downkeyboard_arrow_up
/over-flow/ [ow1.v.er0.f.l.ow2]

Definition: (Especially of a liquid) flow over the brim of a receptacle

Example sentences:

  • chemicals overflowed from a storage tank

43 overshadow keyboard_arrow_downkeyboard_arrow_up
/over-shad-ow/ []

Definition: Appear more prominent or important than

Example sentences:

  • With just five weeks to go before the midterm elections, the talk of war appears to be overshadowing other issues, such as the economy and Social Security.

44 oversized keyboard_arrow_downkeyboard_arrow_up
/over-sized/ [ow1.v.er0.s.ay2.z.d]

Definition: Bigger than the usual size

Example sentences:

  • He was wearing an oversized leather jacket.

45 overwhelming keyboard_arrow_downkeyboard_arrow_up
/over-whelm-ing/ []

Definition: Very great in amount

Example sentences:

  • The government must unite behind this policy, which is supported by the overwhelming majority of the nation.

46 ozone keyboard_arrow_downkeyboard_arrow_up
/ozone/ [ow1.z.ow2.n]

Definition: (O3))A colourless unstable toxic gas with a pungent odour and powerful oxidizing properties

Example senences:

  • The four usual agents of deterioration in the air apart from oxygen and water are sulphur dioxide, hydrogen sulphide, ozone and nitrogen dioxide